Core



3924" .41. A. BYERZS arch M COR-E Filed July 27 inuaizfor Patented Meir.ill, 1924i.

JOHN A. BYERS, OF CHICAGO, ILLINOIS, ASSIGNOR 'I'O JAMES B. GLOW & SONS,OF

' CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

CORE.

Application filed July 27,

To all whom it may concern:

Be it known that 1, JOHN A. BYERS, a citizen of the United States, andresident of Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Cores, of which thefollowing is a full, clear, concise, and exact description, referencebeing had to the accompanying drawing, forming a part of 1 thisspecification.

The present invention relates to molds for casting molten metal and itsprincipal object is the provision of a core es ecially useful in formingthe bell end of pipes cast in a'cent-rifugal casting machine.

In the drawing, Figure 1 is a broken diametrical section of a mold andcore embodying the invention.

Figure 2 is a section on the line 2-2 in Figure 1.

The drawing illustrates a tubular metal mold 1 which is to be suitablymounted. and rotated so that upon introduction of W molten metal in thepreferred manner the pipe 2 will be cast by centrifugal force. The bodyof the pipe 2 is'cast without the use of a core but the peculiarformation of the bell end 3 of the pipe requires'a core for thedefinition of its internal surface, It is usually desirable to form theinternal surface of the bell end of the pipe with an annular groove 4.to receive the lead ring used in packing the joint between contiguouspipe sections in installation. The core for forming the internal surfaceof the bell end of the pipe comprises a tubular metal member 5preferably secured in position by wedges 7 driven throughholes 8 in theend of the mold and wedging the member 5 against an outwardly facingshoulder 6 formed in the mold. 'The bell end 3 of the pipe, of course,will be cast between the internal surface of the mold and the ex-' Iternal surface of the opposed portion of the tubular member 5. In orderto form the annular depression 4 in the pipe and still to permitwithdrawal of the core or tubu- 1922. Serial No. 577,844..

' lar member 5 from the pipe a ring 9 of collapsible material having thedesired conformation is secured on the exterior surface of the metalcore 5. The ring 9 may be formed of any collapsible material, such assand, string or pressed paper, for example, and the metal core 5' isformed with a plurality of vents 10 extending inwardly it will last longenough to form the desired depression in the pipe but will then beburned out. However, whether the ring be formed of such material as willburn out or whether it be formed, for instance, of sand, the metal core5 may be withdrawn 'readily from the pipe and its withdrawal will befacilitated if the inner end of the member be tapered.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

The combination of a tubular metal mold having its internal surfaceformed to mold the exterior surface of a pipe, a tubular metal coreremovably secured to the mold and having its exterior surface formed tomold the internal surface of a pipe and having a surface intersectingthe mold surfaces of the mold and core and formed to mold the end of apipe, and a ring of combustible material projecting from the exteriormolding surface of the core, the core being formed with a plurality ofvents extending from the ring to the bore of the core.

In witness whereof, I hereunto subscribe my name this 24. day of July,1922.

1 JOmT A. BYERS.

